The World of the Ancient Romans
The Byzantine Empire or Eastern Roman Empire, known to its inhabitants as the Roman Empire, the Empire of the Romans (Greek: Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) and also as Romania (Ῥωμανία, Rhōmanía), was the continuation of the Roman Empire during the Middle Ages, centered on its capital of Constantinople, and ruled by Emperors in direct succession to the ancient Roman Emperors. The Empire preserved Romano-Hellenistic traditions, but due to the increasing predominance of the Greek language, it became known to most of its western and northern contemporaries usually as the Empire of the Greeks. In the Islamic world it was known primarily as روم (Rûm "Rome"). The term "Byzantine Empire" was popularized by historians during the 16th – 19th centuries.
The Eastern Roman Empire's evolution from the ancient Roman Empire is sometimes dated from Emperor Constantine I's transfer of the capital from Nicomedia (in Anatolia) to Byzantium on the Bosphorus, which became Constantinople (alternatively "New Rome"). By the 7th century, increased eastern cultural influences, reforms by Emperor Heraclius, and the adoption of Greek as the official language, distinguished the later Roman character from its ancient character.
During its thousand-year existence the Empire remained one of the most powerful economic, cultural, and military forces in Europe, despite setbacks and territorial losses, especially during the Roman–Persian and Byzantine–Arab Wars. After the Komnenian restoration briefly re-established dominance in the 12th century, the Empire slipped into a long decline, with the Byzantine–Ottoman Wars culminating in the Fall of Constantinople and its remaining territories to the Muslim Ottoman Turks in the 15th century.
Division of the Roman Empire
Diocletian created a new administrative system (the tetrarchy). He associated himself with a co-emperor, or Augustus. Each Augustus was then to adopt a young colleague, or Caesar, to share in the rule and eventually to succeed the senior partner. After the abdication of Diocletian and Maximian, however, the tetrachy collapsed, and Constantine I replaced it with the dynastic principle of hereditary succession.
Constantine moved the seat of the Empire, and introduced important changes into its civil and religious constitution. In 330, he founded Constantinople as a second Rome on the site of Byzantium, which was well-positioned astride the trade routes between East and West. Constantine built upon the administrative reforms introduced by Diocletian. He stabilized the coinage (the gold solidus that he introduced became a highly prized and stable currency), and made changes to the structure of the army. Under Constantine, the Empire had recovered much of its military strength and enjoyed a period of stability and prosperity.
Under Constantine, Christianity did not become the exclusive religion of the state, but enjoyed imperial preference, since the Emperor supported it with generous privileges. Constantine established the principle that emperors should not settle questions of doctrine, but should summon general ecclesiastical councils for that purpose. The Synod of Arles was convened by Constantine, and the First Council of Nicaea showcased his claim to be head of the Church.
The state of the Empire in 395 may be described in terms of the outcome of Constantine's work. The dynastic principle was established so firmly that the emperor who died in that year, Theodosius I, could bequeath the imperial office jointly to his sons: Arcadius in the East and Honorius in the West. Theodosius was the last emperor to rule over the full extent of the empire in both its halves.
The Eastern Empire was largely spared the difficulties faced by the West in the third and fourth centuries, due in part to a more firmly established urban culture and greater financial resources, which allowed it to placate invaders with tribute and pay foreign mercenaries. Theodosius II further fortified the walls of Constantinople, leaving the city impervious to most attacks; the walls were not breached until 1204. To fend off the Huns of Attila, Theodosius gave them subsidies (purportedly 300 kg (700 lb) of gold). Moreover, he favored merchants living in Constantinople who traded with the Huns and other foreign groups.
His successor, Marcian, refused to continue to pay this exorbitant sum. However, Attila had already diverted his attention to the Western Roman Empire. After he died in 453, his empire collapsed and Constantinople initiated a profitable relationship with the remaining Huns, who would eventually fight as mercenaries in Byzantine armies. After the fall of Attila, the Eastern Empire enjoyed a period of peace, while the Western Empire collapsed (its end is usually dated in 476 when the Germanic Roman general Odoacer deposed the titular Western Emperor Romulus Augustulus, but declined to replace him with another puppet).
To recover Italy, the emperor Zeno could only negotiate with the Ostrogoths of Theodoric, who had settled in Moesia. He sent the gothic king to Italy as magister militum per Italiam ("commander in chief for Italy"). After the fall of Odoacer in 493, Theodoric, who had lived in Constantinople during his youth, ruled Italy on his own. Thus, by suggesting that Theodoric conquer Italy as his Ostrogothic kingdom, Zeno maintained at least a nominal supremacy in that western land while ridding the Eastern Empire of an unruly subordinate.
In 491 Anastasius I, an aged civil officer of Roman origin, became emperor, but it was not until 498 that the forces of the new emperor effectively took the measure of Isaurian resistance. Anastasius revealed himself to be an energetic reformer and an able administrator. He perfected Constantine I's coinage system by definitively setting the weight of the copper follis, the coin used in most everyday transactions. He also reformed the tax system, and permanently abolished the hated chrysargyron tax. The State Treasury contained the enormous sum of 145,150 kg (320,000 lbs) of gold when he died.
Reconquest of the Western provinces
Justinian I, who assumed the throne in 527, oversaw a period of recovery of former territories. Justinian, the son of an Illyrian peasant, may already have exerted effective control during the reign of his uncle, Justin I (518–527). In 532, attempting to secure his eastern frontier, Justinian signed a peace treaty with Khosrau I of Persia agreeing to pay a large annual tribute to the Sassanids. In the same year, Justinian survived a revolt in Constantinople (the Nika riots) which ended with the death of (allegedly) thirty thousand rioters. This victory solidified Justinian's power. Pope Agapetus I was sent to Constantinople by the Ostrogoths king Theodahad, but failed in his mission to sign a peace with Justinian. However, he succeeded in having the Monophysite Patriarch Anthimus I of Constantinople denounced, despite Empress Theodora's support.
The western conquests began in 533, as Justinian sent his general Belisarius to reclaim the former province of North Africa from the Vandals with an army of about 15,000 men. Success came with surprising ease, but it was not until 548 that the major local independent tribes were subdued. In Ostrogothic Italy, the deaths of Theodoric the Great, his nephew and heir Athalaric, and his daughter Amalasuntha had left her murderer Theodahad on the throne despite his weakened authority. In 535, a small Byzantine expedition sent to Sicily met with easy success, but the Goths soon stiffened their resistance, and victory did not come until 540, when Belisarius captured Ravenna, after successful sieges of Naples and Rome.
Nevertheless, the Ostrogoths were soon reunited under the command of Totila and captured Rome on 17 December 546; Belisarius was eventually recalled by Justinian in early 549. The arrival of the Armenian eunuch Narses in Italy (late 551) with an army of some 35,000 men marked another shift in Gothic fortunes. Totila was defeated and died at the Battle of Busta Gallorum. His successor, Teias, was likewise defeated at the Battle of Mons Lactarius (October 552). Despite continuing resistance from a few Goth garrisons and two subsequent invasions by the Franks and Alamanni, the war for the Italian peninsula was at an end. In 551, a noble of Visigothic Hispania, Athanagild, sought Justinian's help in a rebellion against the king, and the emperor dispatched a force under Liberius, who, although elderly, proved himself a successful military commander. The Byzantine empire held on to a small slice of the Spania coast until the reign of Heraclius.
In the east, Roman-Persian Wars continued until 561 when Justinian's and Khosrau's envoys agreed on a 50-year peace. By the mid-550s, Justinian had won victories in most theaters of operation, with the notable exception of the Balkans, which were subjected to repeated incursions from the Slavs. In 559, the Empire faced a great invasion of Kutrigurs and Sclaveni. Justinian called Belisarius out of retirement, but once the immediate danger was over, the emperor took charge himself. The news that Justinian was reinforcing his Danube fleet made the Kutrigurs anxious, and they agreed to a treaty which gave them a subsidy and safe passage back across the river. Justinian became universally famous because of his legislative work, remarkable for its sweeping character. In 529 a ten-man commission chaired by John the Cappadocian revised the ancient Roman legal code, creating the new Corpus Juris Civilis, a collection of laws that came to be referred to as "Justinian's Code".
During the 6th century, the traditional Greco-Roman culture was still influential in the Eastern empire with prominent representatives such as the natural philosopher John Philoponus. Nevertheless, the Christian philosophy and culture were in the ascendant and began to dominate the older culture. Hymns written by Romanos the Melode marked the development of the Divine Liturgy, while architects and builders worked to complete the new Church of the Holy Wisdom, Hagia Sophia, designed to replace an older church destroyed in the course of the Nika revolt. Hagia Sophia stands today as one of the major monuments of architectural history. During the 6th and 7th centuries the Empire was struck by a series of epidemics, which would greatly devastate the population, contributing to a significant economic decline and weakening of the Empire.
After Justinian died in 565, his successor, Justin II refused to pay the large tribute to the Persians. Meanwhile, the Germanic Lombards invaded Italy; by the end of the century only a third of Italy was in Byzantine hands. Justin's successor, Tiberius II, choosing between his enemies, awarded subsidies to the Avars while taking military action against the Persians. Though Tiberius' general, Maurice, led an effective campaign on the eastern frontier, subsidies failed to restrain the Avars. They captured the Balkan fortress of Sirmium in 582, while the Slavs began to make inroads across the Danube. Maurice, who meanwhile suceeded Tiberius, intervened in a Persian civil war, placed the legitimate Khosrau II back on the throne and married his daughter to him. Maurice's treaty with his new brother-in-law brought a new status-quo to the east territorially, enlarged to an extent never before achieved by the empire in it's six century history, and much cheaper to defend during this new perpetual peace - millions of solidi were saved by the remission of tribute to the Persians alone. After his victory on the eastern frontier, Maurice was free to focus on the Balkans, and by 602 after a series of successful campaigns he had pushed the Avars and Slavs back across the Danube.
Collapse of the Western Roman Empire
In the 5th - 7th century, the Eastern Roman or Byzantine Empire was a continuation of the Roman Empire. The loss of the Western territories in the 5th century led to the loss of some important cities such as Rome. The creation of the Germanic states of the Franks, Visigoths, Ostrogoths and later of the Lombards out of the rubble of the Western Roman Empire meant that in time they would seek to challenge the authority of the Eastern Roman Empire. General Flavius Belisarius under Justinian I in the early 6th century made a serious attempt to recover the western half; however his gains were short-lived and poorly planned out - resources and troops that could have been used to defeat the Persians were diverted forcing the Byzantines into tribute and diplomacy to deal with this Eastern threat. The loss of the western territories led to the Patriarch of Rome achieving greater independence from Byzantium, which no longer provided adequate protection to the Pope. Consequently, the Holy See and Byzantium would have disagreements, culminating in the schism of 1054 sanctioning Latin invasions of Byzantium in the 13th century.